Steel pipes for water and gas supply. Water and gas pipes (VGP): types, characteristics, application Non-galvanized steel pipe gost

INTERSTATE STANDARD

STEEL PIPES
WATER AND GAS PIPELINES

TECHNICAL CONDITIONS

Date of introduction 01.01.77

This standard applies to non-galvanized and galvanized steel welded pipes with threaded or rolled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of plumbing and gas pipelines.

1. VARIETY

1.1. Pipes are made according to the dimensions and weight given in table. 1.

At the request of the consumer, pipes of a light series, intended for thread rolling, are manufactured according to the dimensions and weight given in table. 2.

1.2. The length of the pipe is made from 4 to 12 m:

a) measured or multiple measured lengths with an allowance for each cut of 5 mm and a maximum deviation for the entire length plus 10 mm;

b) unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of off-gauge pipes.

Table 1

Conditional pass	Outside diameter	Pipe wall thickness			Weight of 1 m pipes, kg
Conditional pass	Outside diameter		ordinary	reinforced		ordinary	reinforced

table 2

Conditional pass	Outside diameter	Wall thickness	Weight of 1 m pipes, kg








Notes: 1. For a thread made by the knurling method on a pipe, it is allowed to reduce its inner diameter up to 10% along the entire length of the thread. 2. The mass of 1 m of pipes is calculated at a density of steel equal to 7.85 g / cm 3. Galvanized pipes are heavier than non-galvanized ones by 3%.

1.3. Limit deviations in pipe dimensions should not exceed those indicated in table. 3.

Table 3

Pipe dimensions		Pipe dimensions	Limit deviations for pipes manufacturing accuracy
Pipe dimensions	increased	Pipe dimensions		increased
		Outside diameter with nominal bore:
		over 40 mm
up to 40 mm incl.		Wall thickness
Notes: 1. The maximum deviation to the plus side in the wall thickness is limited by the maximum deviations in the mass of the pipes. 2. Pipes of normal manufacturing accuracy are used for water pipelines, gas pipelines and heating systems. Pipes of increased manufacturing accuracy are used for parts of water and gas supply structures.

1.4. Maximum deviations in pipe weight should not exceed +8%.

At the request of the consumer, the maximum deviations in weight should not exceed:

7.5% - for the party;

10% - for a separate pipe.

(Modified edition, Amendments No. 2, 5).

1.5. The curvature of pipes for 1 m of length should not exceed:

2 mm - with nominal bore up to 20 mm inclusive;

1.5 mm - with a nominal bore over 20 mm.

1.6. The pipe threads can be long or short. The requirements for the thread must correspond to those indicated in table. 4.

Table 4

Conditional passage, mm	Thread length to run		Nominal bore, mm	Number of threads at conditional passage	Thread length to run
Conditional passage, mm		short	Nominal bore, mm	Number of threads at conditional passage		short

1.7. Pipes with a nominal bore of 6, 8, 10, 15 and 20 mm are wound into coils at the request of the consumer.

Legend examples

Ordinary pipe, non-galvanized, of normal manufacturing accuracy, off-gauge length, with a nominal bore of 20 mm, wall thickness of 2.8 mm, without thread and without coupling:

The same with the clutch:

The same, measured length, with thread:

The same, with zinc coating, off-gauge length, with thread:

The same, with zinc coating, measured length, with thread:

For pipes for thread rolling, the letter H is indicated after the word "pipe" in the symbol.

For pipes with long threads, the letter D. is indicated in the symbol after the word "pipe".

For pipes of increased manufacturing accuracy, the letter P. is indicated in the symbol after the size of the conditional passage.

(Modified edition, Amendment No. 1).

2. TECHNICAL REQUIREMENTS

2.1. Pipes are manufactured in accordance with the requirements of this standard and according to the technological regulations approved in the prescribed manner, from steels according to GOST 380 and GOST 1050 without standardizing mechanical properties and chemical composition.

Pipes for parts of water and gas supply structures are made of steels in accordance with GOST 1050.

2.2. At the request of the consumer, the ends of pipes to be welded with a wall thickness of 5 mm or more must be chamfered at an angle of 35 - 40 ° to the end of the pipe. In this case, an end ring with a width of 1 - 3 mm should be left.

At the request of the consumer, on ordinary and reinforced pipes with a nominal bore of more than 10 mm, the thread is applied to both ends of the pipe.

2.1; 2.2.

2.3. At the request of the consumer, pipes are completed with couplings made in accordance with GOST 8944, GOST 8954, GOST 8965 and GOST 8966 at the rate of one coupling for each pipe.

(Modified edition, Amendment No. 3).

2.4. Cracks, captivity, swelling and sunsets are not allowed on the pipe surface.

No delamination is allowed on the pipe ends.

Separate dents, ripples, risks, traces of stripping and other defects caused by the production method are allowed, if they do not take the wall thickness beyond the minimum dimensions, as well as a layer of scale that does not interfere with inspection.

On pipes made by furnace welding, it is allowed to reduce the outer diameter to 0.5 mm at the seam if there is a shallow thickening in this place of not more than 1.0 mm along the inner diameter.

(Modified edition, Amendments No. 3, 4).

At the request of the consumer, on pipes with a nominal bore of more than 15 mm, made by furnace welding and by the method of hot reduction, a gently sloping thickening with a height of no more than 0.5 mm is allowed on the inner surface of the pipes in the seam zone.

(Modified edition, Amendments No. 2, 3, 4, 5, 6).

By agreement between the manufacturer and the consumer, burrs up to 1 mm are allowed on pipes with a nominal bore of 6 - 25 mm made by furnace welding.

(Modified edition, Amendments No. 4, 6).

2.7. Galvanized pipes must have a continuous zinc coating over the entire surface with a thickness of at least 30 microns. The absence of zinc coating on the ends and threads of the pipes is allowed.

On the surface of galvanized pipes, blistering and foreign inclusions (hard zinc, oxides, sintered mixture), peeling of the coating from the base metal are not allowed.

Separate flux spots and traces of pipe gripping by lifting devices, roughness and minor local influx of zinc are allowed.

It is allowed to correct individual non-galvanized sections by 0.5% of the outer surface of the pipe in accordance with GOST 9.307.

(Modified edition, Amendments No. 3, 4).

2.8. The pipes must be able to withstand the hydraulic pressure:

2.4 MPa (25 kgf / cm 2) - pipes, ordinary and light;

3.1 MPa (32 kgf / cm 2) - reinforced pipes.

At the request of the consumer, pipes must withstand a hydraulic pressure of 4.9 MPa (50 kgf / cm 2)

(Modified edition, Amendments No. 2, 3, 5).

At the request of the consumer, pipes must withstand the expansion test:

for pipes with nominal bore from 15 to 50 mm - not less than 7%;

for pipes with a nominal bore of 65 and more - at least 4%.

At the request of the consumer, the pipes must withstand the flattening test up to a distance between flattened surfaces equal to 2/3 of the outer diameter of the pipes.

(Modified edition, Amendments No. 2, 3, 5).

2.10. At the request of the consumer, the mechanical properties of pipes for parts of water and gas pipelines must comply with GOST 1050.

2.11. The pipe thread must be clean, without flaws and burrs and comply with GOST 6357, accuracy class B.

Pipes with cylindrical threads are used in assembly with seals.

2.10; 2.11. (Modified edition, Amendments No. 3, 4).

2.12. At the seam, blackness on the threads is allowed if the reduction in the normal height of the thread profile does not exceed 15%, and at the request of the consumer does not exceed 10%.

Threads with stripped (for cut) or incomplete (for rolled) threads are allowed on the thread, provided that their total length does not exceed 10% of the required thread length, and at the request of the consumer does not exceed 5%.

(Modified edition, Amendments No. 2, 3, 5).

2.13. It is allowed on the thread to reduce the useful thread length (without runaway) up to 15% compared to that indicated in table. 4, and at the request of the consumer up to 10%.

(Modified edition, Amendments No. 2, 3, 5).

2.14. Threading on galvanized pipes is carried out after galvanizing.

2.15. (Deleted, Amendment No. 3).

2.16. At the request of the consumer, pipe welds are subjected to non-destructive testing.

(Modified edition, Amendment No. 5).

3. RULES OF ACCEPTANCE

3.1. Pipes are accepted in batches. A batch must consist of pipes of the same size, of the same brand and be accompanied by one quality document in accordance with GOST 10692 with an addition for pipes intended for the manufacture of parts of water supply and gas pipelines, made of steel in accordance with GOST 1050: chemical composition and mechanical properties of steel in accordance with document on the quality of the manufacturer of the workpiece.

The mass of the batch is not more than 60 tons.

(Modified edition, Amendments No. 3, 4).

3.2. The surface, dimensions and curvature are checked for each pipe in the batch.

It is allowed to apply statistical control methods according to GOST 18242 * with a normal level. Control plans are established by agreement between the manufacturer and the consumer.

* GOST R 50779.71-99 is in force on the territory of the Russian Federation.

Control of the outer diameter of pipes is carried out at a distance of at least 15 mm from the end of the pipe.

(Modified edition, Amendments No. 3, 4, 5).

3.3. To control the parameters of the thread, for testing for expansion, flattening, bending, the height of the internal burr, the remnants of burrs, the right angle and the chamfer angle (for pipes with beveled edges), mechanical properties, take no more than 1%, but not less than two pipes from the batch, and for pipes made by continuous furnace welding, two pipes per batch.

(Modified edition, Amendments No. 3, 4).

3.4. All pipes are subject to weight control.

(Modified edition, Amendment No. 3).

3.5. Each pipe is subjected to a hydraulic pressure test. With 100% quality control of the weld by non-destructive methods, it is allowed not to carry out a hydraulic pressure test. At the same time, the ability of the pipes to withstand the test hydraulic pressure is guaranteed.

(Modified edition, Amendment No. 6).

3.6. To check the thickness of the zinc coating on the outer surface and in accessible places on the inner surface, two pipes are taken from the batch.

(Modified edition, Amendment No. 2).

3.7. Upon receipt of unsatisfactory test results for at least one of the indicators for it, a repeated test is carried out on a double sample.

Retest results apply to the entire batch.

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test.

The tensile test is carried out in accordance with GOST 10006. Instead of tensile testing, it is allowed to carry out control of mechanical properties by non-destructive methods.

(Modified edition, Amendments No. 3, 6).

4.2. Inspection of the pipe surface is carried out visually.

4.3. The hydraulic test is carried out in accordance with GOST 3845 with holding under test pressure for at least 5 s.

4.4. The bend test is carried out in accordance with GOST 3728. Galvanized pipes are tested prior to coating.

(Modified edition, Amendment No. 3).

4.4a. The extension test is carried out in accordance with GOST 8694 on a tapered mandrel with a taper angle of 6 °.

Testing on a mandrel with a taper angle of 30 ° is allowed.

(Modified edition, Amendments No. 3, 4).

4.4b. The flattening test is carried out according to GOST 8695.

(Modified edition, Amendment No. 3).

4.4c. The control of the welded seam is carried out by non-destructive methods according to the normative and technical documentation.

(Introducedadditionally, rev. No. 3).

4.5. The thickness of the zinc coating on the outer surface and in accessible places of the inner surface is controlled in accordance with GOST 9.301 and GOST 9.302, as well as with devices of the MT-41NTs, MTZON type or the "Impulse" type according to the normative and technical documentation.

4.6. The thread is checked with threaded ring gauges in accordance with GOST 2533 (third class of accuracy).

In this case, the screw-in capacity of the no-pass ring gauge on the thread should be no more than three turns.

(Modified edition, Amendments No. 3, 4).

4.7. The curvature of the pipes is controlled with a straight edge in accordance with GOST 8026 and a set of probes in accordance with NTD.

(Modified edition, Amendments No. 3, 5).

4.8. The right angle of the pipe ends is controlled with a 90 ° square with a size of 160 × 100 mm, class 3 GOST 3749, plate probes set 4 according to NTD or a goniometer

Date of introduction 01.01.1977

1. VARIETY

1.1. Pipes are made according to the dimensions and weight given in table. 1.

At the request of the consumer, pipes of a light series, intended for thread rolling, are manufactured according to the dimensions and weight given in table. 2.

1.2. The length of the pipe is made from 4 to 12 m:

Measured or multiple measured lengths with an allowance for each cut of 5 mm and a longitudinal deviation for the entire length plus 10 mm;
- unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of off-gauge pipes.

Table 1

Conditional pass	Outside diameter	Wall thickness			Weight of 1 meter, kg
Conditional pass	Outside diameter	lungs	conventional	reinforced	lungs	conventional	reinforced
6	10,2	1,8	2,0	2,5	0,37	0,40	0,47
8	13,5	2,0	2,2	2,8	0,57	0,61	0,74
10	17,0	2,0	2,2	2,8	0,74	0,80	0,98
15	21,3	2,35	-	-	1,10	-	-
15	21,3	2,5	2,8	3,2	1,16	1,28	1,43
20	26,8	2,35	-	-	1,42	-	-
20	26,8	2,5	2,8	3,2	1,50	1,66	1,86
25	33,5	2,8	3,2	4,0	2,12	2,39	2,91
32	42,3	2,8	3,2	4,0	2,73	3,09	3,78
40	48	3,0	3,5	4,0	3,33	3,84	4,34
50	60	3,0	3,5	4,0	4,22	4,88	6,16
65	75,5	3,2	3,5	4,0	5,71	7,05	7,88
80	88,5	3,5	4,0	4,5	7,34	8,34	9,32
90	101,3	3,5	4,0	4,5	8,44	9,60	10,74
100	114	4,0	4,5	5	10,85	12,15	13,44
125	140	4,0	4,5	5,5	13,42	15,04	18,24
150	165	4,0	4,5	5,5	15,88	17,81	21,63

table 2

Conditional pass	Outside diameter	Wall thickness	Weight 1 m, kg
10	16	2,0	0,69
15	20	2,5	1,08
20	26	2,5	1,45
25	32	2,8	2,02
32	41	2,8	2,64
40	47	3,0	3,26
50	59	3,0	4,14
65	74	3,2	5,59

For a thread made by the knurling method, on a pipe it is allowed to reduce its inner diameter by up to 10% along the entire length of the thread.
The mass of 1 m of pipes is calculated with a steel density equal to 7.85 g / cm3. Galvanized pipes are heavier than non-galvanized ones by 3%.

1.3. Limit deviations in pipe dimensions should not exceed those indicated in table. 3.

Table 3

The maximum deviation to the plus side in the wall thickness is limited by the maximum deviations in the mass of the pipes.
Pipes of conventional manufacturing accuracy are used for water pipelines, gas pipelines and heating systems. Pipes of increased manufacturing accuracy are used for parts of water and gas pipelines.

1.4. Maximum deviations in pipe weight should not exceed +8%.

At the request of the consumer, the maximum deviations in weight should not exceed:

7.5% - for the party;
+ 10% - for a separate pipe.

1.5. The curvature of pipes for 1 m of length should not exceed:

2 mm - with nominal bore up to 20 mm inclusive;
1.5 mm - with a nominal bore over 20 mm.

1.6. The pipe threads can be long or short. The requirements for the thread must correspond to those indicated in table. 4.

Table 4

Conditional pass	Number of threads at conditional passage	Thread length to run, mm
Conditional pass	Number of threads at conditional passage	long	short
6	-	-	-
8	-	-	-
10	-	-	-
15	14	14	9
20	14	16	10,5
25	11	18	11
32	11	20	13
40	11	22	15
50	11	24	17
65	11	27	19,5
80	11	30	22
90	11	33	26
100	11	36	30
125	11	38	33
150	14	42	36

1.7. Pipes with a nominal bore of 6, 8, 10, 15 and 20 mm are coiled into coils at the request of the consumer.

Legend examples

Ordinary pipe, non-galvanized, of normal manufacturing accuracy, off-gauge length, with a nominal bore of 20 mm, wall thickness of 2.8 mm, without thread and without coupling:
Pipe 20x2.8 GOST 3262-75

The same with the clutch:
Pipe М-20х2,8 GOST 3262-75

The same, measured length, with thread:
Pipe Р-20х2,8-4000 GOST 3262-75

The same, with zinc coating, off-gauge length, with thread:
Pipe Ts-R-20x2.8 GOST 3262-75

The same, with zinc coating, measured length, with thread:
Pipe Ts-R-20x2.8-4000 GOST 3262-75

For pipes for thread rolling, the letter H is indicated after the word "pipe" in the symbol.
For pipes with long threads, the letter D. is indicated in the symbol after the word "pipe".
For pipes of increased manufacturing accuracy, the letter P. is indicated in the symbol after the size of the conditional passage.

2. TECHNICAL REQUIREMENTS

Pipes for parts of water supply and gas supply structures are made of steel in accordance with GOST 1050.

2.2. At the request of the consumer, the ends of the pipes to be welded with a wall thickness of 5 mm or more must be chamfered at an angle of 35-40 ° to the end of the pipe. In this case, an end ring with a width of 1-3 mm should be left.

At the request of the consumer, on ordinary and reinforced pipes with a nominal bore of more than 10 mm, the thread is applied to both ends of the pipe.

2.3. At the request of the consumer, pipes are completed with couplings made in accordance with GOST 8944, GOST 8954, GOST 8965 and GOST 8966, at the rate of one coupling for each pipe.

2.4. Cracks, captivity, swelling and sunsets are not allowed on the pipe surface.

No delamination is allowed on the pipe ends.

On pipes made by furnace welding, it is allowed to reduce the outer diameter to 0.5 mm at the seam if there is a shallow thickening in this place of not more than 1.0 mm along the inner diameter.

By agreement between the manufacturer and the consumer, on pipes with a nominal bore of 6-25 mm, made by furnace welding, burrs up to 1 mm are allowed.

2.7. Galvanized pipes must have a continuous zinc coating over the entire surface with a thickness of at least 30 microns. The absence of zinc coating on the ends and threads of the pipes is allowed.

On the surface of galvanized pipes, blistering and foreign inclusions (hard zinc, oxides, sintered mixture), peeling of the coating from the base metal are not allowed.

Separate flux spots and traces of pipe gripping by lifting devices, roughness and minor local influx of zinc are allowed.

It is allowed to correct individual non-galvanized sections by 0.5% of the outer surface of the pipe in accordance with GOST 9.307.

2.8. The pipes must be able to withstand the hydraulic pressure:

2.4 MPa (25 kgf / cm 2) - ordinary and light pipes;
3.1 MPa (32 kgf / cm 2) - reinforced pipes.
At the request of the consumer, the pipes must withstand a hydraulic pressure of 4.9 MPa (50 kgf / cm 2).

At the request of the consumer, pipes must withstand the expansion test:

for pipes with a nominal bore from 15 to 50 mm - at least 7%;
for pipes with a nominal bore of 65 mm and more - at least 4%.
At the request of the consumer, the pipes must withstand the flattening test up to a distance between flattened surfaces equal to 2/3 of the outer diameter of the pipes.

2.10. At the request of the consumer, the mechanical properties of pipes for parts of water and gas pipelines must comply with GOST 1050.

2.11. The pipe thread must be clean, without flaws or burrs and comply with GOST 6357, accuracy class B.

Pipes with cylindrical threads are used in assembly with seals.

2.12. In the place of the seam, blackness on the threads is allowed if the reduction in the normal height of the thread profile does not exceed 15%, and at the request of the consumer does not exceed 10%.

2.13. It is allowed on the thread to reduce the useful thread length (without runaway) up to 15% compared to that indicated in table. 4, and at the request of the consumer - up to 10%.

2.14. Threading on galvanized pipes is carried out after galvanizing.

2.16. At the request of the consumer, pipe welds are subjected to non-destructive testing.

3. RULES OF ACCEPTANCE

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, of the same steel grade and be accompanied by one quality document in accordance with GOST 10692 with an addition for pipes intended for the manufacture of parts of water supply and gas pipelines, from steel in accordance with GOST 1050 chemical composition and mechanical properties of steel - in accordance with the document on the quality of the manufacturer of the workpiece.

Lot weight - no more than 60 tons.

3.2. The surface, dimensions and curvature are checked for each pipe in the batch.

It is allowed to apply statistical control methods according to GOST 18242 with a normal level. Control plans are established by agreement between the manufacturer and the consumer.

Control of the outer diameter of pipes is carried out at a distance of at least 15 mm from the end of the pipe.

3.3. To control the parameters of the thread, for testing for expansion, flattening, bending, the height of the internal burr, the remnants of burrs, the right angle and the chamfer angle (for pipes with beveled edges), mechanical properties, take no more than 1%, but not less than two pipes from the batch and for pipes made by continuous furnace welding, two pipes per batch.

3.4. All pipes are subject to weight control.

3.6. To check the thickness of the zinc coating on the outer surface and in accessible places on the inner surface, two pipes are taken from the batch.

3.7. Upon receipt of unsatisfactory test results for at least one of the indicators, repeated tests are carried out on a double sample.

Retest results apply to the entire batch.

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test.

Tensile testing is carried out in accordance with GOST 10006. Instead of tensile testing, it is allowed to carry out control of mechanical properties by non-destructive methods.

4.2. Inspection of the pipe surface is carried out visually.

4.3. The hydraulic test is carried out in accordance with GOST 3845 with holding under test pressure for at least 5 s.

4.4. The bend test is carried out in accordance with GOST 3728. Galvanized pipes are tested before coating.

4.4-a. The extension test is carried out in accordance with GOST 8694 on a tapered mandrel with a taper angle of 6 °. Testing on a mandrel with a taper angle of 30 ° is allowed.
4.4-b. The flattening test is carried out according to GOST 8695.
4.4-in. The control of the weld is carried out by non-destructive methods according to the normative documentation.

4.5. The thickness of the zinc coating on the outer surface and in accessible places on the inner surface is controlled in accordance with GOST 9.301 and GOST 9.302, as well as with devices of the MT-41NTs, MTZON or Impulse type according to regulatory documents.

4.6. The thread is checked with threaded ring gauges in accordance with GOST 2533 (third class of accuracy). In this case, the screwing capacity of the no-through ring gauge on the thread should be no more than three turns.

4.7. The curvature of the pipes is controlled with a straight edge according to GOST 8026 and a set of probes according to ND.

4.8. The right angle of the pipe ends is controlled with a 90 ° square with a size of 160-100 mm of class 3 in accordance with GOST 3749, plate probes set 4 in accordance with ND or a goniometer in accordance with GOST 5378. The bevel angle of the chamfer is controlled with a protractor in accordance with GOST 5378.

4.9. Outside diameter control is carried out with smooth micrometers according to GOST 6507, calibers-staples according to GOST 2216 or GOST 18360.

The wall thickness, the height of the inner burr and the height of the burrs are measured with a micrometer according to GOST 6507 or a wall gauge according to GOST 11358 from both ends of the pipe. The length of the pipes is measured with a tape measure in accordance with GOST 7502. The thread is controlled with gauges in accordance with GOST 2533.

The mass control of a batch of pipes is carried out on a scale of no more than 10 tons at a division price of no more than 20 kg.

4.10. Weld control is carried out by non-destructive methods according to technical documentation.

5. LABELING, PACKAGING, TRANSPORTATION AND STORAGE

5.1. Marking, packaging, transportation and storage are carried out in accordance with GOST 10692 with the addition.
5.1.1. The pipe thread must be protected from mechanical damage and corrosion with a lubricant according to regulatory documents.

Includes changes # 1, 2, 3, 4, 5, 6 approved in January 1987, May 1988, November 1989, November 1991 2-90, 2-92)

There are many types of shaped products with a round profile. Plastic products (including composite ones) have become a serious competitor to traditional metal pipes. But, despite the versatility of using polymer samples, in the conditions of laying routes outside buildings, when using "iron" in a number of pressure systems, there is still no alternative. This article is about the features and characteristics of water and gas pipes (WGP).

TU for VGP are determined in years. It will not be difficult for anyone who wants to understand the issue more thoroughly. But since both the terminology and most of the parameters are incomprehensible to an ordinary consumer (therefore, they are not interesting), and some are not so significant, we will restrict ourselves only to the main characteristics that are of practical importance in the installation and operation of a water supply system or a gas supply system.

Features of water and gas pipes

The material is high quality steel. Pipes can be without a protective coating or. The latter are used for the installation of structures (circuits), the operation of which will take place in conditions of excessive humidity. All workpieces are welded, which increases their strength.

The main advantages of water and gas pipes:

Mechanical strength.
Long service life.

Availability is allowed:

Small indentations that do not reduce Dy or wall thickness.
Risk.
Spot stripping marks.
Dross.

Signs of marriage

Bulges on the pipe.
Cracks.
Chips, seizures on the end parts.
Exfoliation of the coating on "galvanized".

Characteristics of AIV

The main linear parameters are in "mm".

Length (m): 4 - 12.

By agreement with the customer, in a batch of water and gas pipes, it is allowed to have off-gauge products not exceeding 5% of the total (length within 1.5 - 4 m).

Du: 6 - 150.

Dн: 10.2 - 165.

Wall thickness (limit): for lung pipes (L) 1.8 - 4; ordinary (O) 2 - 4.5; reinforced (U) 2.5 - 5.5.

Maximum hydraulic pressure (MPa): categories L and O - 25, reinforced pipes - 32.

At the request of the customer - up to 50.

Weight 1 r.m. (kg): 0.37 - 15.88 (pipes L); 0.4 - 17.81 (O); 0.47 - 21.43 (Y).

The mass of galvanized pipes is 3% higher than the value of the same parameter for samples without a protective coating.

Decoding of VGP marking

Positions

Type of pipe: M - with coupling, R - with thread, C - with zinc coating, P - increased accuracy, D - long thread, H - knurled.
Wall thickness.
Length (only measured).
GOST number.

Example 32 x 4 GOST 3262-75 - non-galvanized, unmeasured length, regular accuracy, Du \u003d 32, wall \u003d 4. Ts-R-32 x 4 GOST-6000 3262-75 - the same product with thread, galvanized, measured length 6 m.

Application of water and gas pipes

Primary:

In heating systems (circuits), hot water supply, cold water supply, gas supply.
For pumping liquid and gaseous media in production.

Secondary:

Taking into account the high cost of production, zealous owners often give VGP blanks a "second life".

Structural reinforcement elements.
Awnings.
Fencing.
Jumpers and the like.

Price of steel pipes VGP

Depends on many factors, so it is appropriate to give only a few examples of the cost (in rubles / r.m.).

15 x 2.8 - within 56 (galvanized - 94).
"Twenty" with the same wall - 74 (coated - 113).
57 x 3 - 187 (308).
76 x 3.5 - 212 (388).

The water and gas pipe will be made of steel for a long time. Alternative options - metal-plastic water conduits, ceramic, can be used only in certain areas: local water supply systems, gravity sewerage, communication inside the building. However, with above-ground installations, the pipeline is exposed to too much weather. This excludes the use of plastic or other products.

Characteristics of AIV

Water and gas pipes are made from steel billets - strips, by molding. The edges of the workpiece are welded. The seam is reinforced. Inspection of the seam is the first task of quality control, as it is a high-risk area. According to GOST 3262-75, radiography is used to determine the quality.

Water and gas pipes, as a rule, are made longitudinally, since for these products, the more important quality is resistance to internal pressure, and not resistance to external loads. The photo shows a gas pipeline.

Benefits:

high strength, which allows the products to be used with any installation method and in any areas;
oxygen and gas impermeability are precisely the properties due to which gas pipelines are and will be built only from steel products;
low coefficient of expansion - changes in temperature and moisture do not affect the material. The pipeline does not expand, which allows the use of rigid fastening and does not require the device of compensating devices;
durability - with proper maintenance it is 50 years;
affordable cost.

Disadvantages:

rather large weight, which complicates installation and requires a large amount of fasteners;
the need for preventive maintenance - the metal accumulates electricity;
the need for thermal insulation when laying in the ground - the freezing liquid expands, while the parameters of the water conduit remain unchanged. This leads to damage and tearing.

VGP parameters

Dimensions and possible deviations are regulated by GOST 3262-75.

Outside diameter - from 33 to 165 mm.
Wall thickness - from 1 to 5.5 mm.
Length - off-gauge ranges from 4 to 12 m, measured 4–8 or 8–12 m.

Since we are talking about water pipes, instead of the size of the inner diameter, an indicator such as the nominal bore is used. It is given in both inches and mm.

Varieties of products

Different pipeline laying methods and different operating conditions imply different technical characteristics from each other. Hire produces several modifications.

Material classification

The raw material for the manufacture of water and gas pipes is carbon steel of various grades. At the same time, GOST 3262-75 regulates two types of products:

water conduits made of steel of ordinary precision - only the mechanical qualities of the product are controlled. The chemical composition of the steel is not studied. The products are used for household communication systems;
high-precision steel pipeline - galvanized steel is used in the manufacture, mechanical properties are standardized by GOST 3262-75. The products are used in the construction of large highways, where high pressure resistance is important.

In fact, both types of water and gas pipes are made of steel, but pass different levels of control. As a result, they get:

black - without galvanizing, are often used when laying gas lines;
galvanized - finished products are galvanized - immersed in zinc melt. A protective layer is formed on the inner and outer surfaces of the product, which protects against corrosion. Large water mains are constructed of galvanized HDPE.

Release form

Water and gas pipe GOST 3262-75 is produced:

with threaded ends (knurling or cutting) - it is worth noting that the protective layer is damaged during welding, and therefore galvanized products are mounted only by the threaded method;
without thread - a welded joint is assumed.

Resistant to hydraulic pressure

The wall thickness of the water and gas pipeline determines the strength and resistance to a certain hydraulic pressure. The classification is as follows:

light - the working pressure of the liquid should not exceed 25 kg / kV. cm;
ordinary - assumes the same pressure, but allows water hammer;
reinforced - pressure can reach 32 kg / kW. cm.

GOST 7502-98

GOST 8026-92

GOST 8694-75

GOST 8695-75

GOST 8944-75

GOST 8954-75

GOST 8965-75

GOST 8966-75

GOST 10006-80

GOST 10692-80

GOST 11358-89

GOST 18242-72

GOST 18360-93

6. The limitation of the validity period was removed by the Resolution of the State Standard of 12.11.91 N 1726

7. EDITION (May 2007) with Amendments No. 1, 2, 3, 4, 5, 6, approved in November 1977, December 1978, January 1987, May 1988, November 1989. , November 1991 (IUS 1-78, 2-79, 4-87, 8-88, 2-90, 2-92)

This standard applies to non-galvanized and galvanized steel welded pipes with threaded or rolled cylindrical threads and without threads used for water and gas pipelines, heating systems, as well as for parts of plumbing and gas pipelines.

(Modified edition, Rev. N 2, 3, 5).

1. VARIETY

1.1. Pipes are manufactured according to the sizes and weights given in Table 1.

At the request of the consumer, pipes of a light series intended for thread rolling are manufactured according to the dimensions and weight given in Table 2.

(Modified edition, Rev. N 1, 3).

1.2. The length of the pipe is made from 4 to 12 m:

measured or multiple measured lengths with an allowance for each cut of 5 mm and a longitudinal deviation for the entire length plus 10 mm;

unmeasured length.

By agreement between the manufacturer and the consumer, up to 5% of pipes with a length of 1.5 to 4 m are allowed in a batch of off-gauge pipes.

Table 1

Dimensions, mm


Conditional pass	Outside diameter	Pipe wall thickness			Weight of 1 m pipes, kg
		lungs	ordinary	reinforced		ordinary	reinforced

table 2

Dimensions, mm


Conditional pass	Outside diameter	Wall thickness	Weight of 1 m pipes, kg

Notes:

1. For a thread made by the knurling method, on a pipe it is allowed to reduce its inner diameter up to 10% along the entire length of the thread.

2. The mass of 1 m of pipes is calculated with a steel density equal to 7.85 g / cm. Galvanized pipes are 3% heavier than non-galvanized ones.

1.3. Limit deviations in pipe dimensions should not exceed those indicated in table 3.

Table 3


Pipe size	Maximum deviation for pipes of manufacturing accuracy
	ordinary	increased
Outside diameter with nominal bore:
up to 40 mm incl.	0.4 mm -0,5
over 40 mm
Wall thickness

Notes:

1. The maximum deviation to the plus side in the wall thickness is limited by the maximum deviations in the mass of the pipes.

2. Pipes of normal manufacturing accuracy are used for water pipelines, gas pipelines and heating systems. Pipes of increased manufacturing accuracy are used for parts of water and gas pipelines.

1.4. Maximum deviations in pipe weight should not exceed + 8%.

At the request of the consumer, the maximum deviations in weight should not exceed:

+ 7.5% - for the party;

+ 10% - for a separate pipe.

(Modified edition, Rev. N 2, 5).

1.5. The curvature of pipes for 1 m of length should not exceed:

2 mm - with nominal bore up to 20 mm inclusive;

1.5 mm - with a nominal bore over 20 mm.

1.6. The pipe threads can be long or short. Thread requirements should be as specified in Table 4.

Table 4


Nominal bore, mm	Number of threads at conditional passage	Thread length to run, mm
		long	short

1.7. Pipes with a nominal bore of 6, 8, 10.15 and 20 mm are coiled at the request of the consumer.

Legend examples

Ordinary pipe, non-galvanized, of normal manufacturing accuracy, off-gauge length, with a nominal bore of 20 mm, wall thickness of 2.8 mm, without thread and without coupling:

Pipe 20x2.8GOST 3262-75

The same with the clutch:

Pipe M-20x2.8GOST 3262-75

The same, measured length, with thread:

Pipe P-20x2.8-4000GOST 3262-75

The same, with zinc coating, off-gauge length, with thread:

Pipe Ts-R-20x2.8GOST 3262-75

The same, with zinc coating, measured length, with thread:

Pipe Ts-R-20x2.8-4000GOST 3262-75

For pipes for thread rolling, the letter H is indicated after the word "pipe" in the symbol.

For pipes with long threads, the letter D. is indicated in the symbol after the word "pipe".

For pipes of increased manufacturing accuracy, the letter P. is indicated in the symbol after the size of the conditional passage.

(Modified edition, Amendment N 1).

2. TECHNICAL REQUIREMENTS

2.2. At the request of the consumer, the ends of pipes to be welded with a wall thickness of 5 mm or more must be chamfered at an angle of 35 ° -40 ° to the end of the pipe. In this case, an end ring with a width of 1-3 mm should be left.

At the request of the consumer, on ordinary and reinforced pipes with a nominal bore of more than 10 mm, the thread is applied to both ends of the pipe.

2.1, 2.2. (Changed edition, Amendments N 3, 4).

2.3. At the request of the consumer, the pipes are completed with couplings made in accordance with GOST 8944, GOST 8954, GOST 8965 and GOST 8966, at the rate of one coupling for each pipe.

(Modified edition, Amendment N 3).

2.4. Cracks, captivity, swelling and sunsets are not allowed on the pipe surface.

No delamination is allowed on the pipe ends.

Separate dents, ripples, risks, traces of stripping and other defects caused by the production method are allowed, if they do not take the wall thickness beyond the minimum dimensions, as well as a layer of scale that does not interfere with inspection.

On pipes made by furnace welding, it is allowed to reduce the outer diameter to 0.5 mm at the seam if there is a shallow thickening in this place of not more than 1.0 mm along the inner diameter.

(Changed edition, Amendments N 3, 4).

2.5. At the request of the consumer, on pipes with a nominal bore of 20 mm or more, on the inner surface of the pipe seam, the burr must be cut or flattened, while the height of the burr or its traces should not exceed 0.5 mm.

At the request of the consumer, on pipes with a nominal bore of more than 15 mm, made by furnace welding and by the method of hot reduction, a gently sloping thickening with a height of no more than 0.5 mm is allowed on the inner surface of the pipes in the seam zone.

(Modified edition, Rev. N 2, 3, 4, 5, 6).

2.6. Pipe ends must be cut at right angles. The bevel of the butt is allowed not more than 2 °. Burr residues should not exceed 0.5 mm. When removing burrs, the formation of bluntness (rounding) of the ends is allowed. Pipe cutting in the mill line is allowed.

By agreement between the manufacturer and the consumer, on pipes with a nominal bore of 6-25 mm, made by furnace welding, burrs up to 1 mm are allowed.

(Modified edition, Amendments N 4, 6).

2.7. Galvanized pipes must have a continuous zinc coating over the entire surface with a thickness of at least 30 microns. The absence of zinc coating on the ends and threads of the pipes is allowed.

On the surface of galvanized pipes, blistering and foreign inclusions (hard zinc, oxides, sintered mixture), peeling of the coating from the base metal are not allowed.

Separate flux spots and traces of pipe gripping by lifting devices, roughness and minor local influx of zinc are allowed.

It is allowed to correct individual non-galvanized sections by 0.5% of the outer surface of the pipe in accordance with GOST 9.307.

(Changed edition, Amendments N 3, 4).

2.8. The pipes must be able to withstand the hydraulic pressure:

2.4 MPa (25 kgf / cm) - ordinary and light pipes;

3.1 MPa (32 kgf / cm) - reinforced pipes.

At the request of the consumer, pipes must withstand a hydraulic pressure of 4.9 MPa (50 kgf / cm).

2.9. Pipes with a nominal bore up to 40 mm inclusive must withstand the bend test around a mandrel with a radius equal to 2.5 of the outer diameter, and with a nominal bore of 50 mm - on a mandrel with a radius equal to 3.5 of the outer diameter.

At the request of the consumer, pipes must withstand the expansion test:

for pipes with a nominal bore from 15 to 50 mm - at least 7%;

for pipes with a nominal bore of 65 mm and more - at least 4%.

At the request of the consumer, the pipes must withstand the flattening test up to a distance between flattened surfaces equal to 2/3 of the outer diameter of the pipes.

2.8, 2.9. (Modified edition, Rev. N 2, 3, 5).

2.10. At the request of the consumer, the mechanical properties of pipes for parts of water and gas pipelines must comply with GOST 1050.

2.11. The pipe thread must be clean, without flaws and burrs and comply with GOST 6357, accuracy class B.

Pipes with cylindrical threads are used in assembly with seals.

2.10, 2.11. (Modified edition, Amendments N 3, 4).

2.12. At the seam, blackness on the threads is allowed if the reduction in the normal height of the thread profile does not exceed 15%, and at the request of the consumer does not exceed 10%.

Threads with stripped (for cut) or incomplete (for rolled) threads are allowed on the thread, provided that their total length does not exceed 10% of the required thread length, and at the request of the consumer does not exceed 5%.

2.13. It is allowed on the thread to reduce the useful thread length (without runaway) up to 15% compared to that indicated in Table 4, and at the request of the consumer - up to 10%.

2.12, 2.13. (Modified edition, Rev. N 2, 3, 5).

2.14. Threading on galvanized pipes is carried out after galvanizing.

2.15. (Deleted, Amendment No. 3).

2.16. At the request of the consumer, pipe welds are subjected to non-destructive testing.

(Modified edition, Amendment N 5).

3. RULES OF ACCEPTANCE

3.1. Pipes are accepted in batches. The batch must consist of pipes of the same size, of the same steel grade and be accompanied by one quality document in accordance with GOST 10692 with an addition for pipes intended for the manufacture of parts of water supply and gas pipelines, made of steel in accordance with GOST 1050; chemical composition and mechanical properties of steel - in accordance with the quality document of the manufacturer of the workpiece.

Lot weight - no more than 60 tons.

(Changed edition, Amendments N 3, 4).

3.2. The surface, dimensions and curvature are checked for each pipe in the batch.

It is allowed to apply statistical control methods according to GOST 18242 * with a normal level. Control plans are established by agreement between the manufacturer and the consumer.
________________
* On the territory of the Russian Federation, GOST R 50779.71-99 is in force.

Control of the outer diameter of pipes is carried out at a distance of at least 15 mm from the end of the pipe.

(Modified edition, Amendments N 3, 4, 5).

3.4. All pipes are subject to weight control.

(Modified edition, Amendment N 3).

3.5. Each pipe is subjected to a hydraulic pressure test. With 100% quality control of the weld by non-destructive methods, it is allowed not to carry out hydraulic pressure testing. At the same time, the ability of pipes to withstand the test hydraulic pressure is guaranteed.

(Modified edition, Amendment N 6).

3.6. To check the thickness of the zinc coating on the outer surface and in accessible places on the inner surface, two pipes are taken from the batch.

(Modified edition, Amendment N 2).

3.7. Upon receipt of unsatisfactory test results for at least one of the indicators, repeated tests are carried out on a double sample.

Retest results apply to the entire batch.

4. TEST METHODS

4.1. For quality control, one sample is cut from each selected pipe for each type of test.

The tensile test is carried out in accordance with GOST 10006. Instead of tensile testing, it is allowed to carry out control of mechanical properties by non-destructive methods.

(Modified edition, Amendments N 3, 6).

4.2. Inspection of the pipe surface is carried out visually.

4.3. The hydraulic test is carried out in accordance with GOST 3845 with holding under test pressure for at least 5 s.

4.4. The bend test is carried out in accordance with GOST 3728. Galvanized pipes are tested prior to coating.

(Modified edition, Amendment N 3).

4.4a. The extension test is carried out in accordance with GOST 8694 on a tapered mandrel with a taper angle of 6 °.

Testing on a mandrel with a taper angle of 30 ° is allowed.

(Changed edition, Amendments N 3, 4).

4.4b. The flattening test is carried out according to GOST 8695.

(Modified edition, Amendment N 3).

4.4c. Weld control is carried out by non-destructive methods in accordance with regulatory documents

(Introduced additionally, Amendment No. 3).

4.6. The thread is checked with threaded ring gauges in accordance with GOST 5378 from both ends of the pipe.

The length of the pipes is measured with a tape measure in accordance with GOST 7502. The thread is controlled with gauges according to GOST 2533.

The mass control of a batch of pipes is carried out on a scale of no more than 10 tons with a graduation price of no more than 20 kg.

(Modified edition, Amendment N 3, 4, 5, 6).

4.10. Weld control is carried out by non-destructive methods according to technical documentation.

(Introduced additionally, Amendment N 4).

5. LABELING, PACKAGING, TRANSPORTATION AND STORAGE

5.1. Marking, packaging, transportation and storage are carried out in accordance with GOST 10692 with the addition.

5.1.1. The pipe thread must be protected from mechanical damage and corrosion with a lubricant according to regulatory documents.

Section 5. (Modified edition, Amendment N 3).

Electronic text of the document
prepared by Kodeks JSC and verified by:
official publication
M .: Standartinform, 2007